Rotary impeller type impact apparatus



Nov. 17, 1964 F. E. RATH ROTARY IMPELLER TYPE IMPACT APPARATUS original Filed Nov. 12, 1960 5 Sheets-Sheet l Nov. T7, 1964 F, E, RATH 3,157,367

ROTARY IMPELLER TYPE IMPACT APPARATUS Original Filed Nov. l2, 1960 5 Sheets-Sheet 2 INVENTOR. F rank E. Rath BY wuz; nl M F fg 6 HIS ATTORNEYS Nov. 17, 1964 F. E. RATH 3,157,367

ROTARY IMPELLER TYPE IMPACT APPARATUS Original Filed Nov. 12, 1960 5 Sheets-Sheet 5 5 Frank E. Hath BY Ww 41.4% gw H/s ATTORNEYS Nov. 17, 1964 F. E. RATH 3,157,367

ROTARY IMPELLER TYPE IMPACT APPARATUS Original Filed Nov. 12,' 1960 5 Sheets-Sheet 4 I6 JNVENToR. Fl g. Fran/r E. Ram

g BY

WM5/I7( *MM H/s Arron/v5 Ys Nov. 17, 1964 F, E. RATH ROTARY IMPELLER TYPE IMPACT APPARATUS 5 Sheets-Sheet 5 Original Filed Nov. 12, 1960 INVENTOR. Fran/r E. Rath g. l5 By HIS ATTORNEYS United States Patent O 3,157,367 RTARY IMIELLER TYPE ACT APPARATUS Frank E. Rath, Butler, Pa., assignor to Spring @a Company, Butler, Pa., a corporation of Pennsylvania Continuation of application Ser. No. 71,100, Nov. 12, 1960. This application Aug. 22, 1963, Ser. No. 306,983 21 Qlaims. (Ci. 24h-274) This invention relates to a rotary impeller type impact crushing apparatus for breaking up or shattering friable materials which may contain sizeable pieces of metal or other relatively non-crushable materials.

This application is a continuation of my copending application Serial No. 71,100 filed November l2, i969, now abandoned, which, in turn, is a continuation-impart of my application Serial No. 739,823, iiled lune 4, 195 8, now Patent No. 2,971,703, which in turn is a continuation-inpart of my application Serial No. 674,255, filed July 25, 1957, now forfeited. Y

One application of my invention deals with rotary impeller impactor means or apparatus for breaking up friable portions of a process burden containing pieces of noncrushable material bound by the friable portions. The burden may be of a form such as is found in metal bearing steel plant slags or other metal bearing steel plant debris and may contain magnetic and non-magnetic metal pieces, magnetic oxides, refractories and slags. In such burden, at least a portion of the metal is contained in or adheres to a binder material such kas the slag or refractories.

To recover the metals and other valuable portions from such a process burden, I have found that it is necessary to break up this burden in such a manner as to free the metal from the non-metallic content and, in effect, free various portions of the content with respect to each other. The purpose of such treatment is to product a resultant process burden whose larger size portion consists mainly of clean malleable metal pieces and whose smaller size portion consists of the balance of the material which includes particles of metal previously held in association with the friable binder materials. Apparatus used for this purpose must be capable of breaking up the friable portions of such a process burden to a relatively small size and freeing the non-crushable metallic content from adheiing friable materials. Such an apparatus must also be capable of withstanding the abrasive action of this type of process burden and be capable of freely discharging the large pieces of non-crushable metals after impacting.

I have found that there is a particular need for an impacting apparatus of this type in successfully carrying out a reclamation procedure such as set forth in my Patent No. 2,971,703 entitled Process for Cleaning and Recovering Scrap Metal From Slag and the Like. l have found that impact crushing apparatus heretofore available in the artis not suitable for this purpose. Apparatus heretofore available has been of a combination shear and impact type where the rotor blades shear out a portion of the incoming burden and impact crushing occurs on the rotor blade face. Both of these actions concentrate wear on the rotor which is the most difficult and expensive part of the equipment to maintain. Even when modied to partially eliminate the shearing action of the rotor, the equipment is inefficient, undependable, excessively expensive as to initial investment and maintenance costs, unable to maintain the continuity of operation required in the type of service described in my Patent No. 2,971,703, and does not efliciently convert input rotational energy to impact energy. Further, the prior art makes no provision to pass large pieces of non-crushable material as is evidenced by progressive reductions of internal clearance in most equipment in an attempt to gather the uncrushed 3,l57,367 Patented Nov. 17, 1964 material into an area of active impaction. The elfort is made in the prior art to reduce all material to a given size or sizes before discharging it. This is not desirable or possible in the service described in my above-mentioned patent.

One of the salient features of my invention is the novel concept of using the rotating impeller as a means of imparting a high kinetic energy to the incoming burden by accelerating it to a high velocity. The impact energy available is according to the formula ma2 E where m is the mass of the object and v is the velocity of the object. To the initial velocity of the incoming particle is added the velocity of the impeller blade tip and the particle is projected at a high rate of speed toward a massive impact wall. At the moment of impact, the kinetic energy due to the velocity is transformed into energy of impact with a subsequent rupturing or pulverization of the particle. If a particle is composed of two or more different types of matter, the kinetic energy of each type will vary directly with the mass of the matter since the entire particle is traveling at the same high velocity. At the moment of impact, the unbalanced forces set up by the differences in energies cause a rupturing or cleavage along the boundaries between the different types of matter as the heavier material attempts to continue along its path with greater energy than the lighter matter. In this manner, an efcient disruption is performed between the heavier particle content and the relatively lighter portion. Further, by introducing the incoming material to the rotor in such a manner as to obtain acceleration rather than impaction at the rotor blade face, the zone of severe wear is removed from the relatively delicately balanced and expensive rotor to a massive, easily replaced impact surface.

An object of my invention is to solve the various problems involved in an apparatus utilization such as here involved and to provide a practical operating arrangement.

Another object of my invention is to device a new and improved form of impaction apparatus, essentially of a rotary type that will meet the requirements of continuous operation involved in my Patent No. 2,971,703.

A further object of my invention is to provide impaction apparatus capable of practical utilization at a Wide range of speeds and blade velocities to effect a substantially complete breaking up of friable materials into suitable size ranges Without excessive wear on expensive and diiiicult to maintain parts.

A still further object of my invention is to provide a relatively inexpensive, wear resistant, and easily maintained, as well as highly eilicient, operating apparatus for crushing or breaking up a process burden.

These and other objects of my invention will be apparent to those skilled in the art from the exemplary embodiment as shown in the drawings and the description thereof.

In the accompanying drawings which illustrate a preferred embodiment of my invention,

FIGURE 1 is a side elevation of an apparatus constructed in accordance with my invention;

FIGURE lA is a greatly reduced side view in elevation of the housing of the apparatus showing its anged side panel construction;

FIGURE 2 is a view taken along the line II--II of FIGURE 1; Y

FIGURE 3 is a vertical section taken along the line III- III of FIGURE 2;

FIGURE 4 is an enlarged vertical sec-tion through the rotor of FIGURES 1 to 3 showing details of its construction;

FIGURE 5 is 'an'elevation of the rotor shown in FIGURE 4 taken on the line V-V of FIGURE 4 but on a reduced scale;

FIGURE 6 is a fragmental section taken along the line VI-VI of FIGURE 4 but on an enlarged scale;

FIGURE 7 is an enlarged perspective view showing the construction of a wedge key employed with the mounting pin of FIGURE 6;

FIGURE 7A is an enlarged perspective view of a retaining key employed with the mounting pin of FIG- URE 6;

FIGURE 8 is a vertical section taken on the line VIII-VIII of FIGURE 1, the rotor, end bearings and supports for the end bearings being removed;

FIGURE 9 is an end elevation taken along the line IX-IX of FIGURE l, parts being removed;

FIGURE 10 is a broken away top plan View of the structure shown in FIGURE l;

FIGURE ll is a horizontal section taken on the line XI-XI of FIGURE l;

FIGURE l2 is an enlarged end view of the rotor taken n the line XII-XH of FIGURE 5; and

FIGURE 13 is a greatly enlarged fragmental section taken on the line XIII-XIII of FIGURE 12.

Referring more particularly to the accompanying drawings, my rotary impact apparatus comprises a housing indic-ated generally by reference numeral 2 forming an impact chamber B in which a rotary impeller indicated generally by the reference numeral 4 is located. The housing comprises two side walls 6 and 6a, a rear wall 8, a top wall 10, and a front wall made up of various parts which will be described more particularly hereinafter,

The two side walls 6 and 6a are similar to each other, the right-hand side wall 6 being shown in FIGURE 1A. The side walls 6 and 6a rest at their lower edges on longitudinal I beams 12 and the rear wall 8 and the front wall rest on transverse I beams 13. The beams 12 and 13 are supported on concrete piers (not shown) which extend above floor level, thus providing an outlet opening D (See FIGURES 8 and l1) for the material which has been impacted. The lower end of each of the side walls 6 and 6a has an outwardly extending flange 16 integral with it, this flange being secured to the beams 12 by bolt and nut assemblies 18. The upper edge of each of the side walls 6 and 6a (see FIGURE 1) is provided with an integral outwardly extending flange 20 and the upper edge of the rear wall 8 has a rearwardly extending flange 22 integral therewith. The rear wall 8 is reinforced by two vertical ribs 9 and at its lower edge has a rearwardly extending integral flange 23 which is secured to beam 13 by fasteners 23a. The top wall 10 is secured to the side walls and end wall by bolt and nut assemblies 24. The top wall has a rectangular inspection opening 26 formed in it which is closed by a removable cover 28, the upper frame portion 30 of which spans the joint between the cover 28 and the top wall 10 to seal it. The frame 30 is provided with lifting lugs 32 and the top wall 10 is provided with lifting lugs 34.

Referring now more particularly to FIGURES 1, 1A and 8, the lower front portion of each of the side walls 6 and 6a is provided with a slot 36 which is open at its front end. At the border of this slot, each of the side plates is provided with outwardly extending flanges, there being an upper horizontal flange 38, two vertical flanges 40, a lower horizontal flange 42 and a flange 44 connecting the flange 42 with the flange 16. The front lower end of the housing is closed by a removable cover 46 provided With lifting lugs 47. This cover has a forwardly extending flange 48 at its top which is secured by fasteners 50 to a flange member 39 connected between flanges 38 of the side walls 6 and 6a and a ange 48a at its bottom which is secured to beam 13 by fasteners 56a. The ends of the cover 46 are secured to the flanges 44 and 80 by fasteners 52 and 88.

The impeller 4 is keyed to a shaft S4 by a key S6 (see FIGURE 4) and the ends of the shaft 54 extend through the slots 36 in the housing side walls 6 and 6a and are rotatably mounted in bearing housings 58 as shown in FIGURE 2. Each of the bearing housings 58 is mounted on a filler block 60 which is supported on a support 62 which in turn is supported by and secured to the flange 16. The filler blocks 60 are secured to the bearing housing SS and to the supports 62 by removable fasteners 64 and the filler blocks are provided with hand grips 66 so that they may be removed from beneath the bearing housings and supports after the fasteners 64 are removed. A drive wheel 68 driven by any suitable source of power, not shown, is secured to the impeller shaft 54.

In order to seal the space between the shaft 54 and the border of the slot 36, a removable side plate 70 and a removable shaft seal plate 72 are provided. These parts are shown in their withdrawn positions in FIGURE 1 in dotted lines. The side plate 7G has a cutout portion 74 adapted to llt around the shaft S4. The side plate 70 has a top flange 76, a bottom flange 78 (see FIGURE 8), a front end flange 80 and two rear end flanges 82, these flanges being provided with bolt receiving openings 84. The side plate 70 fits within and is bolted to the flanges 38, 40 and 42 of the side walls 6 and 6a by fasteners 86. It also is secured to the removable cover 46 by fasteners 8S. The shaft seal plate 72 ts into the space 90 between the ends of the flanges 40 (see FIGURE 1A). Each of the shaft seal plates 72 has a curved portion 73 adapted to fit shaft 54 and is secured in shaft sealing position to one of the side walls 6 and 6a of the housing by means of fasteners 92.

In order to remove the impeller 4, impeller shaft 54 and drive wheel 68 as a unit from the housing 2, the cover 46 and removable side plate 70 are moved to the left as shown in FIGURE 1 in dotted lines after removing the fasteners which secure them to the housing. The shaft seal plate 72 may or may not be moved to the dotted line position shown in FIGURE 1 as desired. The flller blocks 60 which support the bearing housings S8 are removed after relieving pressure on them and the shaft 54 lis lowered until it rests on the flanges 42 of the side walls 6 and 6a which serve as rails, after which the rotor can be rolled while its shaft is supported on the flanges 42 onto rails (not shown) located outside of the housing. In'FIGURE 1A, the shaft 54 is shown in full lines in the normal operating position of the rotor and is shown in dotted lines when it is resting on the flanges 42 so that it may be rolled along the anges and removed from or entered into the housing.

Referring particularly to FIGURES 1, 1A, 2 and 3, each of the side walls 6 and 6a has an upwardly and forwardly extending external flange 94. The housing at its upper left-hand end as viewed in FIGURE 1 is provided with a support flange 96 surrounding a feed opening A, the flange 96 being fastened to a bottom flange 98 of a feed chute 100 by fasteners 102.

An adjustable guide means 104 for feeding material to be impacted to the rotary impeller 4 is mounted in the housing adjacent its upper left-hand end as shown in FIGURE 1. This guide means comprises a guide plate 106 which is pivoted adjacent its upper end on a rod 108 extending through lugs 110 secured to the underside of the guide plate and through holes in the housing side plates 6 and 6a. The rod is secured in position by cotter pins 112. The lower end of the guide plate 106 is provided with lugs 114 on its underside which receive a rod 116 supported in one or the other of two sets of holes 11S formed in the side walls 6 and 6a and retained in place by cotter pins 120. Thus, the inclination of `the plate 106 can be adjusted depending upon which set of holes receives the rod 116. Preferably, the arrangement for adjusting the inclination of the guide plate 106 is such that the guide plate can be adjusted at inclinations between about 35 and about 55 degrees with respect to the horizontal. In order to provide access to the adjust able guide means 104, a removable cover 121 having hand grips 121a is fastened to the flange 94 by fasteners 121b.

The interiors of the side walls 6 and 6a, the top Wall 10, the removable inspection cover 28 and the material entrance portion 12.2 of the housing are lined with wear resistant steel liner plates 124 (see FIGURE 3) which can be readily and individually removed for repair or replacement as needed. Each of these removable liner plates is provided with stud bolts 126 secured to the liner plate and adapted to be received in openings formed in the housing structure and secured by nuts 128.

The rear wall 8 of the housing is protected by au impact wall designated generally by reference numeral 130 and shown particularly in FIGURES 3 and l0. This wall consists of vertically extending, transversely spaced, wood strips 132 or strips of other stock absorbent material secured to wall 8 by means (not shown) and a wall made up of horizontally extending, vertically stacked, loose steel billets 134. The bottom steel billet is supported on a transverse metal support member 136 secured to the housing 2 and each of the other billetsrests on the billet immediately below it.

The construction of the impeller 4 is shown more particularly in FIGURES 4, 5, 12 and 13. The body 138 of the impeller is cylindrical. It may consist of a single piece or it may consist, as shown, of a number of annular sections 138a welded or otherwise secured together and mounted on the shaft 54. Each end face 140 of the body 138 is provided with an outer ring of curved segments 142 of Wear resistant material, three such segments being shown in FIGURE l2. These segments 142 are provided with holes 144 which receive the ends of stud bolts 146 secured in the body 138 and projecting therefrom. The holes 144 yand stud bolts 146 serve to locate the segments 142 properly on the ends of the body 133. The peripheral tace 148 of the body 138 is covered by a wear resistant l plate 150, the plate 150 being welded at its ends to the end segments 142 as indicated by reference numeral 152. The corners of the body 138 at the edges of the peripheral face 14S and end face 140 are chamfered as indicated by the reference numeral 154 to form a pocket 156. Vent openings 15S in the end segments 142 lead from the exterior of the impeller to the pockets 156. When it is desired to remove the wear resistant plate 150 or the end segments 142 from the body 138 of the impeller, the plates 150 and 142 may be burned olf adjacent the pockets 156 without the heat injuring the body of the impeller. The end segments 142 can then beslid olf of the studs 146 and the plate 156 can be removed from the body 138.

Curved wear resistant plates 160 may be placed inside of curved segments 142 to cover the` inner portion of the end faces 14th, the curved plates 160 being secured to the body 13S by screw bolts 162.

The impeller 4 is provided with a series (three in number as shown in the drawings) of radially extending, circumferentially spaced slots 164 which extend the length of the impeller. `An impeller blade 166 is received in each of the slots 164, a portion of the blade projecting beyond the periphery of the'jrotor. A mounting pin 168 is received in a bore 17th of the body 138, the pin 168 extending through a hole 172 in the inner portion of the irnpeller blade 166. Impeller blade 166 and rotor body 138 are retained in intimate contact with respect to each other by the cooperative reaction of retaining key 174 and wedge key 176 passing through keyholes 174a and 176:1,y

said keyhole having a constant cross sectionahsomewhat ovular shape through the pin 168; Wedgey key 176 (see FIGURE 7) is of a rectangular wedge shape with one v uniformly tapered, rounded edge which cooperates with a similarly tapered keyhole 176a to provide the wedging action between mounting pin 163 and locking bar 178 and thus secure impeller blade 166 with respect to the rotor body 138. As fur-ther shown in FIGURE 7, the convergent end portion of wedge key 176 is slotted at 180 and has a series of threaded portions at 182 to receive a threaded spread bolt 184. In this manner, the slotted portion of the key is vspread to prevent withdrawal from keyhole 176e during operation. The planer edge of key 176 (opposite the rounded, tapered edge) is adapted to be inserted into a machined groove in continuous removable locking bar 173 (see FIGURES 5 and 6) so as to tightly wedge the mounting pin 168 in a blade-retaining position and to prevent rotation of pin 168 about its longitudinal axis. The mounting pins 168 are entered through pockets or slots 192. Bores 194 of smaller diameter than the bores 170 extend through the body 138 to serve as knock-out openings after holes-communicating with the bore 194 have been cut through we-ar plates 150) for removing stuck or jammed pins 168 when an impeller blade 166 is to be removed from the impeller. Wear resistant plates 196 are secured by screws 198 to parts of the body portion 138 adjacent the pockets 192.

In operating the rotary impact apparatus, material to 'be impacted is fed to the feed chute 190, enters feed opening A of impact chamber B, flows over the adjustable guide plate 106 onto the impeller 4. The material is guided and directed in its downward movement by the guide plate 106 so as to meet the periphery of the yrotary impeller 4 at a proper angular relationship with respect to and in the general direciton of the peripheral rotation. In this respect, the guide plate 106 is adjustable to provide an angular relationship of downward material flow of from about 35 to about 55 with respect to a horizontal plane. The delivery of the material upon or toward the impeller is in the nature of a tangential delivery, the angle of which may be varied for maximum efficiency depending upon the size of the material being handled and the speed of rotation of the impeller. By using such a tangential delivery, I avoid shear of the material by the impeller'blades 166 with a consequent reduction of wear on the blades. I impart as high a kinetic energy as pos# sible to the incoming material by increasing its velocity' so that it Will move olf from the impeller somewhat tangentially to impact against the reinforced impact wall 130.

The adjustable entry angle of the guide plate 106 is important and is determined by the impeller speed which in turn is determined by the size range of the incoming burden. In order to avoid excessive shock and wear on the impeller as it contacts larger size pieces of the burden, the impeller is revolved no faster than the speed at which minimum shock on the impeller consistent with ecient operation is obtained. In order to achieve the desired ballistic trajectory at reduced rotor speeds, it then becomes necessary to introduce the incoming burden to the rotor at a point earlier in rotation than is necessary with smaller material. Thus, I may employ amore forward point of delivery upon the impeller 4 (with respect to its direction f of rotation) for smaller size material and a more backward point of delivery upon the impeller for larger maj terial.. The materialV is delivered to the impeller near its top orupper section as distinguished from its lower section or half. It is thrown by the impeller against the impact wall formed of stacked steel billets 134, the friable portion'is crushed and all of the material then drops ldown through the passageway C between kthe impact wall 134 and the impeller tinto and through the outlet opening D in the bottom of the housing 2. f

vI have found thatvth'e size of the free discharge pas sageway C (see FIGURE 3) `in the housing between the tips of rotor 'blades'166 and the impact wall 134 is of importance since theunobstructed area of this passageway and of v.the outlet :opening D must be of a size sufficient to readily or freely pass the largest pieces ofnonbreakable material fed to the impactor without damage to the apparatus.

It will be understood that rotary impacting apparatus as herein disclosed may be built in various sizes dependent upon the specific results expected of the unit as, for example, 40 X 36", 30 X 30", or 24" x 24". When I speak of a 40 x 36" rotary impacting apparatus, I have reference to a unit with a 40" diameter rotor (measured over the rotor blade tips) and a 36 length of rotor body. It has been found practical to employ a 40" x 36" rotary impacting apparatus with a passageway C dimensioned of 30" for impact treatment of material up to about 24" in maximum dimension. Also, it has been found practical to employ a 30 x 30" rotary impacting apparatus with a passageway C dimension of 20 for impact treatment of material up to about 12 in maximum dimension and a 24 x 24 unit with a passageway C dimension of for material up to about 5" to 6" in maximum dimension.

I have successfully employed rotary impacting apparatus as herein described for processing material containing metal pieces up to 24 mesh size. By this I mean material which will pass through a screen or grid having square openings or passes of 24". Although impaction may be used for material sizes below 1" mesh size, I find that the most eicient area of utilization for this particular application is for burdens containing metal pieces in the size range from 1" to 18 mesh size.

Referring particularly to FIGURE 3, the velocity imparted to the material lby the impeller 4 is substantially equal to the velocity of the tips of the impeller blades 166. It can be appreciated that in actual use, the impeller is slowed somewhat when first contacting a heavy particle due to the energy required to accelerate the particle being removed from the rotational energy of the impeller. The impeller quickly regains this energy from the driving motor, not shown, but the momentary slowing causes the heavier particles to be projected on a different trajectory from the lighter particles. In this connection, note the three trajectories indicated by arrows 199, 200 and 201 of FIGURE 3. Depending to a certain extent upon the weight of the particle, its trajectory will be similar to one of the three indicated with the heavier particles striking the impact Wall 130 lower (trajectory 201) than the lighter particles (trajectory 199 or 200) because of the heavier particles later departure from the rotor. It is important then to select an initial rotor speed and angle of guide means 104 which, when treating the particu-l lar range of Isizes and weights of particles fed, will cause the material to travel along trajectories such as 199, 200 and 201 of FIGURE 3 in order to cause all particles to strike the impact wall 130 which is inertially massive and easy to repair according to which of the billets become worn due to impaction of the material.

As previously discussed, with equal particle velocities, greater impact energies are available in the larger, heavier particles so it is thus apparent that the greatest shattering or crushing effect is obtained on the larger size particles such that larger pieces of the friable material are crushed to release and clean the metal content vwhile the smaller size particles have their metal piece content at least partially released from a bound relationship with the friable material and thus are receptive to further impaction in a smaller unit with a different particle size, rotor speed relationship where ultimate release of the metal content will 'be effected. Such serial treatment in Isuccessive units with selectively decreasing particle size andincreasing rotor speeds is fully disclosed in my Patent No. 2,971,703.

From a practical standpoint, I have employed rotor speeds of 200 to 1120 r.p.m. with impeller blade speeds of from 2100 to 7050 f.p.m., using the slower speeds and larger passageway C openings for burdens having a larger maximum size content, and using higher speeds and smaller passageway C openings for burdens having a smaller size piece content. For example, a 40" x 36" rotor operated at a speed of 400 r.p.m. has been found satisfactory for impacting a burden comprising an agglomcrate of metal and slag, Where the agglomerate particle size ranges from 12" to 18" mesh size with a metal piece content thereof up to a maximum of nearly l2 mesh size, to produce a resultant impacted burden of minus 12" mesh size; a 30" x 30 rotor operated at a speed of 500 r.p.m. and a blade speed of 3900 f.p.m. has been found satisfactory for processing a slag and metal burden up to 12" mesh size to provide an output of from 3 to 12" mesh size clean metal and minus 6" mesh size slag; a 30" x 30" rotor operated at a speed of 600 r.p.m. and a blade speed of 4700 f.p.m. has been found satisfactory for processing a burden up to 6I mesh size to provide an output of from 3" to 6 mesh size clean metal and minus 3" mesh size contaminated metal and slag; a 30" x 30" rotor operated at a speed of 900 r.p.m. and a blade tip speed of 7050 f.p.m. has been successfully employed for a burden or aggregate of up to 3 mesh size to provide a resultant burden comprising 1" to 3" mesh size clean metal and minus 1" mesh size slags and contaminated metal; and a 24 x 24" rotor operated at a speed of 1120 r.p.m. and a blade tip speed of 7050 f.p.m. has been found satisfactory for processing a burden of up to 3" mesh size to produce a resultant burden containing from 1% or l up to 3 clean metal and minus 3A or 1'l slag.

From the foregoing disclosure, it will be apparent to those skilled in the art that the employment of my invention is not limited to the particular process burden used for the exemplary embodiment as the device is suitable for shattering, pulverizing or impacting other friable materials with or without included relatively non-shatterable or non-crushable materials, but is especially suited for use where the possibility of such inclusions, whether by chance or design, exists.

The invention is not limited to the preferred embodiment, but may be otherwise embodied or practiced within the scope of the following claims.

I claim:

1. Impact crushing apparatus comprising a housing having side walls, end walls and a top wall defining an impact chamber; means for feeding material to be crushed into said chamber through one of said end walls, said means including an angularly adjustable guide plate; an impact wall located in said impact chamber adjacent the other of said end walls and opposite said material feeding means, said impact wall comprising a plurality of independently replaceable contact members exposed to the interior of said chamber and shock absorbing means between said contact members and said end wall; a rotary impeller within said chamber located in the path of the material fed to said chamber from said guide plate, said guide plate being positioned with respect to said impeller so that the material is delivered to the impeller in a substantially tangential direction; means for rotating said impeller at a selected speed to throw the material against said impact wall, whereby the angle of said guide plate and the speed of said impeller are selected to confine the crushingof the material to said replaceable Contact members and thereby eliminate wear on said side walls and top wall of said chamber.

2. Impact crushing apparatus comprising a housing having side walls, end walls and a top wall defining an impact chamber; means for feeding material to be crushed into said chamber through one of said end walls, said means including an angularly adjustable guide plate; a vertical impact wall located in said impact chamber adjacent the other of said end walls and opposite said material feeding means, said impact wall comprising a pluralityfof loosely stacked contact members; a rotary impeller within said chamber located in the path of the material fed to said chamber from said guide plate, said guide plate being positioned with respect to said impellcr so that the material is delivered to the impeller in a substantially tangential direction; means for rotating said impeller at a selected speed to throw the material against said impact wall, whereby the angle of said guide plate and the speed of said impeller are selected to confine the crushing of the material to the impact wall and thereby eliminate wear on said side walls and top wall of said chamber.

3. Impact crushing apparatus as defined in claim 2 including means removablyattaching said top wall to said side and end walls of the housing, whereby said top Wall may be removed from the housing to replace individual contact members worn by contact with the material.

4, A rotary impeller type impact crusher comprising a housing defining an impact chamber; said impact charnber having side walls, end walls and top and bottom walls; one of said end Walls having an inlet opening for material to be crushed and the other of said end walls comprising an impact wall, spaced outer wall member and shock absorbing means between said impact wall and said outer wallmember; said impact wall consisting of a plurality of vertically stacked horizontal members extending between said side walls, the bottom member of said plurality of vertically stacked members resting on said bottom wall and each of the other members of said plurality of vertically stacked members restrained by gravity on the member immediately therebelow; a rotary impeller within said housing located in the path of the material entering said chamber through said inlet opening; means for rotating said impeller to throw the material against said impact wall; and said bottom wall having an outlet opening for discharging the impacted material from said chamber.

5. A rotary impeller impact type crusher comprising a housing, said housing having side walls, end walls and a top wall defining an impact chamber; one of said end walls vhaving a material inlet opening; a horizontal support member secured to said housing and extending between said side walls at the base of the other of said end walls; an impact wall located adjacent the other of said end walls, said impact wall comprising a plurality of vertically stacked members extending between said side walls, the bottom member of said plurality of vertically stacked members resting on said support member and each of the other members being supported on the member immediately therebelow; a rotary impeller within said chamber adjacent said material inlet opening; means for rotating said impeller; and an outlet defined by said housing at the bottom of said chamber, whereby material entering said chamber through said inlet opening is thrown against said impact wall by said rotary impeller and passes out of said chamber through said outlet after contacting said impact Wall.

6. A Crusher as set forth in claim 5 wherein the top wall of said housing is removably attached to the upper edges of the side and end walls whereby it can be easily removed for selective replacement of different members of said plurality of vertically stacked members.

7. A crusher as set forth in claim 6 wherein the top wall is provided with lifting lugs to facilitate removal thereof when replacement of said vertically stacked members is required.

8. A crusher as set forth in claim S wherein said top wall is removably attached to said housing, and said top wall having an inspection opening therein, said inspection opening being provided with a removable cover, whereby said vertically stacked members can be visually inspected to determine the wear thereon and said removable top wall can be removed to selectively replace worn members.

9. A rotary impeller type impact crusher comprisingl a housing having side walls, end` walls and a top wall defining an impact chamber, one of saidend walls having an inlet opening for the introduction of material to be crushed; means defining an impact surface adjacent the other of saidend walls; an inclined feed chute connected to said inlet opening for supplying material through said opening into said impact chamber; said housing having an outlet opening at the base of said impact surface for discharging impacted material; a rotary impeller in said chamber positioned between said side Walls in the path of material passing through said inlet opening, said impeller including a plurality of blades rigidly secured thereto for propelling the material against said impact surface, the -outer ends of said impeller blades being spaced from said impact surface and forming an unrestricted passageway with said side Walls and said impact surface leading to said outlet opening, the maximum lateral cross section of said feed chute being smaller than the minimumlateral cross section of said unrestricted passageway whereby any piece of non-breakable material entering said chamber through lsaid feed chute can pass through said unrestricted passageway to said outlet opening without jamming said impeller and shearing off said rigidly secured blades.

10. Impact crushing apparatus comprising a housing defining an impact chamber therein and including side walls, a front wall and a bottom, said front wall terminating above said bottom to provide an impeller opening through which an impeller can be introduced into and removed from the housing, a rotary impeller positioned to extend transversely within said housing, each of the side walls of the housing having a slot which is open at the front, an impeller shaft secured to said impeller and extending through said side Walls and received in said slots, bearings for said impeller shaft positioned outside of said housing, removable support means for said bearings, and a fiange secured to and extending outwardly from and along each of said side walls adjacent said slots for supporting said impeller shaft when said removable support means for said bearings is removed, whereby said impeller can be rolled into or out of said housing through said impeller opening while said impeller shaft rests on saidflanges.

11. Apparatus as defined in claim 10, comprising a removable closure for said impeller opening.

12. Apparatus as defined in claim 11, comprising removable side plates cooperating with said iianges and housing to enclose said impeller shaft.

13. Impact crushing apparatus comprising a housing defining an impact chamber therein, a rotary impeller within said housing, means for rotating said impeller, means for feeding material to be impacted to said impeller, said housing including an end wall located in the path of material thrown from said impeller, an impact wall located adjacent said end wall and between said impeller and said end wall, said impact wall comprising loosely stacked metal billets backed by strips of wood interposed between said end wall and said stacked metal billets. Y

14. A rotary impeller comprising a cylindrical body, a series of radially extending slots spaced circumferentially around the periphery of said body and open at said periphery, an impeller blade in each of said radially extending slots and projecting outwardly from said periphery, and means located within the circumference of said body for removably securing said impeller blades in said slots.

15. A rotary impeller comprising a cylindrical body, a series of radially extending slots spaced circumferentially around the periphery of said body and open at said periphery, an impeller blade in each of said radially extending slots and projecting outwardly from said periphery, a series` of mounting pins located within the circumference of said body and extending through said impeller blades to removably secure said impeller blades in said slots, and means for retaining said mounting pins within said body.

16. A rotary impeller according to claim l5 wherein the means for retaining said'mounting pins within said body comprises a retaining key located in said radially extending slot and fitting into a keyhole in said mounting pin, and a wedge key fitting into a keyhole in said mounting pin. n

17. A rotary impeller according to claim 16, wherein the keyholes for said retaining key and wedge key extend.

1 1 through said mounting pin at substantially right angles to each other.

18. A rotary impeller comprising a cylindrical body, a series of radially extending slots spaced circumferentially around the periphery of said body and open at said periphery, an impeller blade in each of said radiallyrextending slots and projecting outwardly from said periphery, means located within Ithe circumference of said body for removably securing said impeller blades in said slots, and removable wear resistant surface members secured to outer portions of said body.

19. A rotary impeller comprising a cylindrical body, a series of radially extending slots spaced circumferentially around the periphery of said body and open at said periphery, an impeller blade in each of said radially extending slots and projecting outwardly from said periphery, means for removably securing said impeller blades in said slots, a wear resistant end member covering at least the radially outer portion of each end of said body, and wear resistant face members covering the face of said body, said wear resistant face members being secured at their ends to said wear resistant end members.

20. A rotary impeller according to claim 19, wherein a corner at the face and end of said cylindrical body is chamfered to provide a pocket which facilitates burning oi said wear resistant members at their meeting edges without injuring said body.

21. A rotary impeller according to claim 19, wherein guide pins secured to said body project from the ends thereof and are received in holes in said wear resistant end members.

References Cited by the Examiner UNITED STATES PATENTS 1,581,684 4/26 Ogden SM1-198.5 2,172,886 l9/39 Gabel 24ll98.5 2,246,902 6/41 Smith 241-275 XR 2,292,852 8/42 \Verner 241--275 XR 2,898,053 8/59 Rogers 241--275 2,981,489 4/61 Hannum 241-275 ANDREW R. JUHASZ, Primary Examiner.

WILLIAM W. DYER, JR., Examiner.

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent Noo 3, 157 ,367 November l7 1964 Frank E Rath n the above numbered patlt is hereby certified that error appears i nt should read as ent requiring correction and' that the said Letters Pate corrected below Column l, column 2, line 4l, for "device lines and 7, for housing" rea for and 6a" read or 6a column 5i line l, for "stock" read shock column line 32, for "direciton" Y. read direction Signed and sealed this 30th day of March 1965.,

(SEAL) Attest:

EDWARD J. BRENNER ERNEST W. SWIDER Attesting Officer Commissioner of Patents 

1. IMPACT CRUSHING APPARATUS COMPRISING A HOUSING HAVING SIDE WALLS, END WALLS AND A TOP WALL DEFINING AN IMPACT CHAMBER; MEANS FOR FEEDING MATERIAL TO BE CRUSHED INTO SAID CHAMBER THROUGH ONE OF SAID END WALLS, SAID MEANS INCLUDING AN ANGULARLY ADJUSTABLE GUIDE PLATE; AN IMPACT WALL LOCATED IN SAID IMPACT CHAMBER ADJACENT THE OTHER OF SAID END WALL AND OPPOSITE SAID MATERIAL FEEDING MEANS, SAID IMPACT WALL COMPRISING A PLURALITY OF INDEPENDENTLY REPLACEABLE CONTACT MEMBERS EXPOSED TO THE INTERIOR OF SAID CHAMBER AND SHOCK ABSORBING MEANS BETWEEN SAID CONTACT MEMBERS AND SAID END WALL; A ROTARY IMPELLER WITHIN SAID CHAMBER LOCATED IN THE PATH OF THE MATERIAL FED TO SAID CHAMBER FROM SAID GUIDE PLATE, SAID GUIDE PLATE BEING POSITIONED WITH RESPECT TO SAID IMPELLER SO THAT THE MATERIAL IS DELIVERED TO THE IMPELLER IN A SUBSTANTIALLY TANGENTIAL DIRECTION; MEANS FOR ROTATING SAID IMPELLER AT A SELECTED SPEED TO THROW THE MATERIAL AGAINST SAID IMPACT WALL, WHEREBY THE ANGLE OF SAID GUIDE PLATE AND THE SPEED OF SAID IMPELLER ARE SELECTED TO CONFINE THE CRUSHING OF THE MATERIAL TO SAID REPLACEABLE CONTACT MEMBERS AND THEREBY ELIMINATE WEAR ON SAID SIDE WALLS AND TOP WALL OF SAID CHAMBER. 